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Livestock manure and related statistics 30 November 2015, Kigali, Rwanda International Workshop on Statistics on nitrogen input from livestock manure: Estimating availability and use
Livestock manure and
related statistics
30 November 2015, Kigali, RwandaInternational Workshop onStatistics on nitrogen input from livestock manure: Estimating availability and use
Outline
The challenge of making agriculture more productive and sustainable
Soil degradation
Causes of soil degradation in Africa
Manure and soil degradation
Statistics on livestock manure: uses and trends at global, regional and sub
regional scale
Conclusions
~800 M people undernourished
World population continues to
grow
Ecosystems and biodiversity
are increasingly stressed
Climate change
Making agriculture more productive and
sustainable
Increase food production in
a sustainable way in the
areas where it is most
needed
Challenge
About 30% of the world soils are moderately to high degraded
About 40% of these soils are located in Africa
Example: Need to reverse soil degradation
Causes of soil degradation in Africa (i)
Very old and weathered soils
The limited fertilizer inputs application have not been able to replace the
nutrients export in yields (Soil nutrient mining)
0
10
20
30
40
50
60
70
1961 1966 1971 1976 1981 1986 1991 1996 2001 2006 2011
Kg
of
N /
ha
/ y
ea
r
Africa Americas Asia
Nutrient depletion rate in SSA
Causes of soil degradation in Africa (ii)
Increased demographic pressure limits
the possibility to leave the land fallow
which used to restore soil fertility
• As a response soil fertility declines
• Poverty trap: low yield, low income, low
inputs
• Relationship between soil degradation
and poverty
Soils in a severe degradation state
are not responsive to nutrient inputs
as plants are no longer able to
capture the nutrients
In these soils large applications of
manure can restore soil health and
the responsiveness of the soils
Similarly, in more responsive soil the
addition of manure can maintain soil
health (integrated nutrient
management)
Manure can have a primary role in supporting crop
production in Africa, reversing soil degradation
Soil heath consists of chemical, physical and biological soil health with
the three dimensions being equally important
The three dimensions of soil health
Physical Soil Health
- Aggregation
- Structure
- Porosity
- Water/Gas
- movement
Chemical Soil Health
- pH
- CEC
- Nutrient
availability
Biological Soil
Health- Macrofauna
- Mesofauna
- Microfauna
- Biological
activity
SOIL
HEALTH
Manure and soil health
Chemical Soil Health
• Macronutrients and
Micronutrients
• C input to soils
• SOM input to soils which
improves cation
exchange capacity, pH
buffering
• Favors nutrient cycling
with the farm
Physical soil health
• The increased SOM
favors soil aggregation
• Reduced bulk density
• Stimulate biological
activity thereby improving
soil structure
Biological soil health
• Increased biological
activity and functional
diversity
• Feed for the soil biota
• The increased SOM
creates a suitable
environment for the soil
biological communities
• Unlike chemical fertilizers, manure has positive effects on the three aspects
of soil health
Environmental impact of manure
Leaching
Run off
Nutrient and C losses
occurs during manure
storage and applications
Net nutrient losses varies
across different manure
management systems,
soil types, environmental
conditions
Ammonia
volatilization, CH4,
N2O, CO2
The importance of improving the statistics on
manure
Manure can have:
– A primary role in supporting crop production, especially in Africa
– Negative impacts on the environment
Improved statistics on livestock manure are needed in order
to:
– Compile comprehensive accountings of the total nutrients input
applied to soils and pastures
– Assess current and potential environmental impact (e.g. GHG)
Improving analysis on livestock manure
through better statistics
Input data• Livestock numbers
• Feed baskets
Coefficients/parameters• Nutrient excretion rates
• Use of manure
• Losses from manure management
systems
Outputs• Nutrient loads on
pastures and
cropland
Manure left on pasture
Manure stored in MMS
Manure burned for fuel
Nutrient losses during manure
management
Nutrient in Manure burned for fuel
Nutrient input from manure left on pasture
Nutrient losses coefficientper each MMS
Nutrient input from manure applied to soils
Nutrient excretion rate
Nutrient excreted
MS
(% o
f m
anu
re
in e
ach
MM
S)
Number of animals
Manure production has increased
from 1961-2012
N input from synthetic fertilizers
increased exponentially and
became the first source of N
worldwide in 1986
Wide variations among regions
Better Data in support of Analysis:
Manure production and uses in the world
-
50
100
150
200
250
1961 1968 1975 1982 1989 1996 2003 2010
Mil
lio
n T
on
nes
of
N
Manure applied to soils Manure left on pasture
Synthetic Fertilizer
2012
14%
39%47%
24%
60%
16%
16%
38%
46%1961
1986
Source: FAOSTAT 2015
Manure production has increased
steadily from 1961-2012
More than 80% of the N input from
manure is left on pasture
While the contribution of the
manure applied to soils is very
limited (3-4%)
Chemical N input has gained
importance but still represents only
about 12% of the total N input
applied
High variability among sub regions
Manure production and uses in Africa
-
20
40
60
1961 1968 1975 1982 1989 1996 2003 2010
Mil
lio
ns
To
nn
es
of
N
Manure applied to soils Manure left on pasture
Synthetic Fertilizers
3%
93%
4%
1961 4%
83%
13%
19864%
83%
12%
2012
Africa
Source: FAOSTAT 2015
0
2
4
6
8
10
12
Mil
lio
ns t
on
nes
of
Nit
rog
en
Synthetic fertilizers Manure left on pasture Manure applied to soil
Manure production and uses in the African
Sub regions
1986 20121961
Source: FAOSTAT 2015
The challenge of eliminating hunger in the context of climate change, limited natural
resources, ecosystem degradation and demographic pressure
Many soils are degraded and manure can help in reversing soil degradation and
maintaining soil health
Manure management and applications can also results in negative environmental
externalities
Therefore improved statistics of manure are relevant both from an agronomic and
environmental point of view
Lasting trends indicated that:
– Globally synthetic fertilizers are the main source of N
– The African N input strongly relies on manure; with the manure left on pasture
being the main source of Nitrogen in all the sub regions
Conclusions
NA is the sub region with the
second highest N input
Greater contribution of synthetic
fertilizers compared with other
African sub regions
Manure left on pasture accounted
for about 73% of the total N input in
2012
Limited amount of manure is
applied to soils
Manure production and uses in Northern Africa
0
3
6
9
12
1961 1968 1975 1982 1989 1996 2003 2010
Mil
lio
ns
To
nn
es
of
N
Manure Applied to soils Manure Left on pasture
Synthetic fertilizers
3%
84%
14%
3%
70%
28%
3%
73%
24%
1961
1986
2012
Northern Africa
Source: FAOSTAT 2015
EA is the region with the highest
N input
Manure left on pasture is the
main N source of N
Limited amount of manure is
applied to soils
N input from synthetic fertilizers
14 times higher in 2012 than in
1961
However synthetic fertilizers only
accounted by 7% of the total N
input
Manure production and uses in Eastern
Africa
0
3
6
9
12
1961 1968 1975 1982 1989 1996 2003 2010
Mil
lio
ns
To
nn
es
of
N
Manure Applied to soils Manure Left on pasture
Synthetic fertilizers
3%
96%
1%
3%
92%
4%
3%
89%
7%
1961
1986
2012
Eastern Africa
Source: FAOSTAT 2015
0
3
6
9
12
1961 1968 1975 1982 1989 1996 2003 2010
Mil
lio
ns
To
nn
es o
f N
Manure Applied to soils Manure Left on pasture
Synthetic fertilizers
Fertilizers increased exponentially in
the last 50 years (more than 100
times)
Still, they only accounted for 8% of
the total N input in 2012
Manure left on pasture was the main
source of N and accounted for about
87% in 2012
Limited amount of manure is applied
to soils
Manure production and application in Western Africa
3%
96%
0%
3%
90%
6%
3%
87%
8%
1961
1986
2012
Source: FAOSTAT 2015
MA is the region with the lowest total
N input
Steady increase of N input from
1961-2012
Manure applied to soils and
synthetic fertilizers increased across
the period considered
Still, the manure left on pasture
represents about 89% of the total N
input in 2012
Manure production and application in Middle Africa
0
3
6
9
12
1961 1968 1975 1982 1989 1996 2003 2010
Mil
lio
ns
To
nn
es
of
N
Middle Africa
Manure Applied to soils Manure Left on pasture
Synthetic fertilizers
3%
94%
1% 7%
90%
3%
7%
89%
3%1961
1986
2012
Source: FAOSTAT 2015
The total N input did not record
remarkable variation in terms of
total tonnage
Significant variation in terms of
N source
Manure left on pasture
decreased from 93% to 73 in
1961 and 2012, respectively
N input form the manure applied
to soils represented only 3% of
the total N input
Synthetic fertilizers increased
considerably reaching 23% of
the total N input in 2012
Manure production and application in Southern Africa
0
3
6
9
12
1961 1968 1975 1982 1989 1996 2003 2010
Mil
lio
ns
To
nn
es
of
N
Southern Africa
Manure Applied to soils Manure Left on pasture
Synthetic fertilizers
3%
93%
4%3%
75%
22%3%
73%
23%
1961
1986 2012
Source: FAOSTAT 2015
